Backstage at The Tonight Show, they make some really, really cool music. They call it the "Cover Room" and what happens there can be pretty freakin' awesome.

Take, for example, last night's (August 17) episode, when Kesha and The Roots covered the classic folk song "The House of the Rising Sun." Most of us are familiar with the 1964 cut by The Animals, but now we just might have a new favorite version.

What happens in that tiny room, along with a few stools, an acoustic guitar and some wildly talented musicians, is hypnotic. Maybe it's the song, maybe it's the singer, maybe it's some invisible ingredient we'll never be able to identify, but... just watch:

And that wasn't the only performance of a classic tune last night. Billy Idol played "White Wedding" on The Late Late Show—and you know what? The '80s rock icon definitely still rocks. (Billy, please do "Cradle of Love" next, thanks!)

Meanwhile, over on The Late Show, Grizzly Bear performed "Mourning Sound." Maybe it's not a classic (yet?), but it's still pretty darn good. Check it out below: